JPH1060698A - Method for cleaning and roughening surface of printed circuit board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for cleaning and roughening the surfaces of printed circuit boards which is helpful for environmental protraction and recycling of resources by cleaning and roughening the surfaces of the printed circuit boards by a reverse electrolysis method, regenerating and cyclically using the sulfuric acid in an electrolyte and recovering the metal reduced and deposited on cathodes. SOLUTION: One or more pieces of electrolytic cells 1 injected with the electrolyte 11 are provided. The cathode plates 2 respectively connected to the negative poles of a power source are immersed and mounted in the respective electrolytic cells 1. The printed circuit boards 3 are connected to the positive poles of the power source and are transferred as an anode so as to be continuously passed in the respective electrolytic cells 1, by which the metals on the surfaces of the printed circuit boards 3 are electrolyzed and are reduced and deposited on the surfaces of the cathode plates 2, by which the copper surfaces of the printed circuit boards 2 are cleaned and roughened by the electrolytic polishing effect.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for cleaning and roughening a metal surface of a printed circuit board. The present invention relates to a method for cleaning and roughening the surface of a printed circuit board having an effect of recycling.

[0002]

2. Description of the Related Art A conventional printed circuit board (PC board) is used to clean and roughen a metal surface such as copper by directly immersing the printed circuit board in a corrosive chemical solution such as an acid solution. The corrosion and polishing action of the chemical solution dissolves impurities on the copper surface of the printed circuit board to clean and roughen the surface.
If the strongly acidic chemical becomes saturated with the dissolved metal as it is used for cleaning, it should be treated as a waste liquid until it is harmless, and then discarded. Or, if it is omitted, it not only causes environmental pollution due to heavy metals but also wastes resources.

[0003]

SUMMARY OF THE INVENTION In view of the above problems in the conventional method for cleaning and roughening the surface of a printed circuit board, the present invention provides
The surface of the printed circuit board is cleaned and roughened by reverse electrolysis, the acid solution of the cleaning agent is recycled and recycled, and the metal deposited and reduced on the cathode is recovered to help prevent environmental pollution and recycle resources. It is an object of the present invention to provide a clean surface roughening method.

[0004]

In order to achieve the above object, the present invention provides a method of immersing a cathode plate connected to a negative electrode of a power source in one or more electrolytic cells into which an electrolytic solution as a detergent is injected. Then, the printed circuit board is connected to the positive electrode of the power supply and transferred so as to continuously pass through each electrolytic cell as an anode. By the action, the surface of the printed circuit board is reversely electrolyzed to be cleaned and roughened at the same time.

[0005] Then, the printed circuit board is continuously transferred by a transfer mechanism including a plurality of rotating rollers arranged at appropriate intervals, and is at an appropriate position near the entrance and exit of the electrolytic cell. A roller is formed on an anode roller connected to a power supply positive electrode and electrically connected to a printed circuit board, and a cathode plate in each of the above-described electrolytic cells is placed above and below a printed circuit board transfer path in each of the electrolytic cells. It is more preferable to attach each one one by one.

According to the present invention having the above structure, one or more electrolytic cells are provided in the transfer path of the printed circuit board, the electrolytic solution 11 is injected into each electrolytic cell, and Since the cathode plate connected to the negative electrode of the power supply is immersed and mounted in the transfer path of the printed circuit board, the metal surface of the printed circuit board passing through the electrolytic cell can be cleaned and roughened by the electrolytic polishing action. .

[0007] The electrolytic solution containing metal ions by the electropolishing action comes into contact with the cathode plate, and the metal can be deposited on the surface of the cathode plate by the deposition action. Since the electrolytic solution is regenerated, it can be recycled. In addition, the metal in the electrolyte can be recovered to avoid environmental pollution.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be specifically described based on embodiments, but the present invention is not limited to these embodiments. As shown in FIG. 1, the present invention mainly includes an electrolytic cell 1 into which one or more electrolytic solutions 11 are injected, and immerses and mounts a cathode plate 2 connected to a negative electrode of a power source in each of the electrolytic cells 1 and performs printing. The circuit board (PC board) 3 is connected to the positive electrode of the power source, transferred as an anode so as to continuously pass through each electrolytic cell 1, and electrolyzes the metal (eg, copper) on the surface of the printed circuit board 3;
The surface of the printed circuit board is cleaned and roughened by an electrolytic polishing action by reducing and depositing on the surface of the cathode plate 2.

Therefore, according to the present invention, one or more electrolytic baths 1 are provided in the transfer path of the printed circuit board 3, and a conductive electrolytic solution 11 is injected into each electrolytic bath 1;
For example, a cathode plate 2, which is a sulfate solution of an electrolytic metal and is used as a conductive medium and is connected to a negative electrode of a power supply, is immersed in a transfer path of a printed circuit board 3 in each electrolytic cell 1. Are mounted above and below the transfer path of the printed circuit board 3 so that reverse electrolysis can be performed on both sides of the printed circuit board 3 at the same time.

The continuous transfer of each printed circuit board 3 is performed by rotating rollers 4 arranged at a plurality of appropriate intervals.
A roller at an appropriate position near the inlet 12 and outlet 13 of each of the electrolytic cells 1 is connected to the positive electrode of the power source and formed on the anode roller 42 by the transfer mechanism 4 comprising The printed circuit board 3 entering the electrolytic cell 1 is made to maintain the electrical property of the anode, whereby the printed circuit board 3 maintaining the anode electrical property electrolyzes the copper metal on the surface thereof in the electrolytic solution 11 of the electrolytic cell 1, In addition, copper metal is reduced and deposited on the surface of the cathode plate 2 in the same electrolytic cell 1, that is, the metal surface of the printed circuit board 3 is electrolyzed to be reduced and deposited on the surface of the cathode plate 2, and the surface of the printed circuit board is cleaned and roughened. It can achieve the purpose of becoming.
On the other hand, since the copper deposited by reduction on the surface of the cathode plate 2 forms a single-layer copper foil, it can be directly peeled off and reused.
Further, since the sulfate electrolyte solution 11 as the electrolytic medium can be repeatedly used repeatedly, environmental pollution of heavy metals or strong acid chemicals is not formed as in the related art.

The electrolytic cell 1 in which the above-mentioned cathode plate 2 is immersed is installed by providing one or many continuously in the transfer path of the printed circuit board 3 depending on the degree to which the surface of the printed circuit board 3 is cleaned and roughened. Alternatively, the electrolytic cell 1 may be provided at an appropriate length so that the required reverse electrolysis clean and roughening effect can be achieved.

[0012]

The present invention configured as described above has the following effects. Since the surface of the printed circuit board is cleaned and roughened by the reverse electrolysis, it can meet the demand for environmental protection and does not cause contamination. The sulfate serving as the electrolyte can be repeatedly used. Copper reduced and deposited on the cathode plate can be directly removed and reused, thereby achieving the purpose of resource recycling. Since the surface roughening method by electrolysis is adopted, a stress concentration deformation phenomenon such as a mechanical surface polishing method on a printed circuit board does not occur.

[Brief description of the drawings]

FIG. 1 is a schematic representation of a preferred embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electrolyzer 11 Electrolyte 12 Entrance to an electrolyzer 13 Outlet from an electrolyzer 2 Cathode plate 3 Printed circuit board (PC board) 4 Transfer mechanism 41 Rotary roller 42 Anode roller

Claims (3)

[Claims] 1. A cathode plate connected to a negative electrode of a power source is immersed in one or more electrolytic cells into which an electrolytic solution as a detergent is injected, and a printed circuit board is connected to a positive electrode of the power source to serve as an anode. It is transferred so as to continuously pass through each electrolytic cell, and the metal on the surface of the printed circuit board is electrolyzed to be reduced and deposited on the surface of the cathode plate. A method for cleaning and roughening the surface of a printed circuit board, which is to be surface-roughened. 2. The continuous transfer of the printed circuit board is performed by a transfer mechanism including a plurality of rotating rollers arranged at appropriate intervals, and is at an appropriate position near the entrance and exit of the electrolytic cell. The method for cleaning and roughening the surface of a printed circuit board according to claim 1, wherein the roller is formed as an anode roller connected to a positive electrode of a power supply and electrically connected to the printed circuit board. 3. The printed circuit board surface according to claim 1, wherein one of the cathode plates in each of the electrolytic cells is attached above and below a printed circuit board transfer path in each of the electrolytic cells. Clean surface roughening method.